Determination of Kinetic Parameters in the Biosorption of Cr (VI) on Immobilized Bacillus cereus M1 16 in a Continuous Packed Bed Column Reactor

Abstract

Due to technological advancement, environment suffers from untreated toxic heavy metal bearing effluent coming from different industries. Chromium (VI) is one of those heavy metals having adverse impact on ecological balance, human, and plant health because of its carcinogenic properties. Biosorption is presented as an alternative to traditional technologies which are costly and inefficient for treatment of industrial wastes containing low amount of heavy metals. In this study, bioremediation of Cr (VI) ions by immobilized Bacillus cereus M(1) (16) was investigated in a laboratory scale packed bed up-flow column reactor. The effect of important parameters, such as the inlet flow rate, influent concentration, and effective bed height, has been studied. External mass transfer, surface adsorption, and intrabead mass transfer were also studied to conclude the rate limiting step for removal of Cr (VI) and to determine the process parameters which are important for biosorption optimization. The external mass transfer coefficient was calculated at different flow rates (6.51 x 10(-2) to 7.58 x 10(-2) cm/min). Using the model, the surface adsorption rate constant (k(ad)) and the intrabead mass transfer coefficient (k (i)) were predicted as 0.0267 x 10(-3) and 0.7465 x 10(-3) l/g/min, respectively. Both are much lower than the external mass transfer coefficient (k(e)). The surface adsorption phenomenon is acting as the rate-limiting step due to its high resistance for removal of Cr (VI).

Metal sorption by algal biomass: From batch to continuous system

“…At 367 mg l −1 of Pb(II), the breakthrough time was~40 min; however, it was~280-290 min when Pb(II) concentration was 79 mg l −1 . Packed column study for the removal of Cr(VI) using B. cereus, a bacterial biosorbent, also made similar observations [85]. Both the breakthrough and saturation time were longer at lower influent concentration of Cr(VI), and shorter at higher influent concentration.…”

“…This fact is also supported in the course of finding a flatter shape of breakthrough curve at high flow rate [54]. However, in the case of Cr(VI) sorption by Bacillus cereus packed column, Maiti et al [85] have demonstrated a steep breakthrough curve for high flow rate. Nonetheless, when the flow rate is very high, the column requires a longer period to reach saturation after attaining breakthrough point [68,128].…”

“…13.5 h to 6.5 h) was noticed for an A. hydrophila biomass packed bed following increase in flow rate from 2 to 10 ml min − 1 [51]. At a high flow rate, the duration metal ion stays in the column is very short, which might not be sufficient for attaining equilibrium of metal sorption process and therefore metal ions run away from the column without binding to any active sites of the biosorbent [85,115]. In other words, the maximum sorption capacity of the column is not exploited efficiently at a high rate of flow of metal solution.…”

Chromium(VI) Biosorption and Bioaccumulation by Live and Acid-Modified Biomass of a NovelMorganella morganiiIsolate

“…A great volume of work exists on the chromium reduction capacities of various organisms (e.g., bacteria (5,7,8,(29)(30)(31)(32) algae (33), and fungi (2,34)). While the use of non-modified live bacteria for bioremediation efforts has been documented, Cr(VI) removal efforts often focus on use of acidified environments and/or acid treated biomass.…”

Analysis and Speciation of Chromium in Environmental Matrices by Various Analytical Techniques

“…In aqueous solution Cr(VI) predominately exists as chromate ion 33 and easily penetrates into biological membranes and cause cellular damage by inducing oxidative stress 79,80 . If Cr(VI) is more than its permeable level (0.05 mg/L) in the domestic water supplies which was set by the US EPA and the European Union 81 , was causes severe diarrhea, ulcers, eye and skin irritation, kidney dysfunction and probably lung carcinoma by accumulating in living tissues throughout the food chain due to its non-biodegradable metallic nature 82,83 . It may also cause renal tubular necrosis, chronic ulceration and perforation of the nasal septum 84 .…”